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Re: Any official clarification on Text-only zoom and RWD?


From: Alastair Campbell
Date: Feb 25, 2016 8:56AM

Guy Hickling wrote:

> The critical bit to have in em units are the media query breakpoints.

Ah, ok. However, the difference in how the layout works on your site works
is the percentages on the columns.

The columns are relative to the window size (e.g. 70% for the main content).

The different between PX and EMs for triggering media queries is pretty
minor in practice, for people who have the default font-size there is no
difference at all as browsers calculate the layout based on pixels (and EM
sizes are calculated to CSS pixels).

If people do change the default font size, and there is a mix of
percentages, EMs and perhaps PX sizes on the page, the proportions of
things can vary unpredictably.

That is ok if you have a simple two column layout, but take a site like a
newspaper (e.g. http://www.theguardian.com).

The main layout has a mix of pictures and text in a complex grid based
layout, that's a lot harder to work with. Any variability in how it behaves
will cause things to break.

I believe the Guardian does size things with EMs completely (or at least
enough), as increasing text-size behaves in the same was as zoom. However,
that doesn't fulfil the requirement for text-only zoom.

Is that really a problem? (_mallory?)

I think it would be unrealistic to allow for both text-sizing and zoom to
work on a layout like that, from a robustness point of view. It would fall
apart too easily.